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Intraplanar Magnetic Excitations in Na0.5CoO2: An Inelastic Neutron Study

J. Wooldridge·G. Balakrishnan·D. McK. Paul·C. Frost·P. Bourges·M. R. Lees
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Abstract

Inelastic neutron scattering measurements mapping the in-plane magnetic interactions of Na0.5CoO2 reveal dispersive excitations at points above an energy gap Eg = 11.5(5) meV at the superstructural Bragg reflections. The excitations are highly damped, broadening with increasing energy, and disappear at hw ~ 35 meV, a strong indication that the magnetism is itinerant. Tilting into the ac plane reduces the value of Eg by 25%, suggesting that the dispersion along c is significant and the magnetic correlations are three-dimensional, as seen at the higher doping levels.

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J. Wooldridge, G. Balakrishnan, D. McK. Paul, C. Frost, P. Bourges, M. R. Lees. 2006-08-11. Intraplanar Magnetic Excitations in Na0.5CoO2: An Inelastic Neutron Study. https://arxiv.org/abs/cond-mat/0608196

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